Some practical issues in time domain passivity control of haptic interfaces
نویسندگان
چکیده
In this paper, two major practical issues are studied to improve the performance of a new energy based method of achieving stable, high performance haptic interface control. The first issue is related to resetting the amount of energy accumulated in the Passivity Observer for faster operation. A heuristic method is derived and experimentally tested for the resetting and it is shown to help the PC to operate sooner when the system gets active. The second one was noise in velocity measurements being magnified into audible force signals by the controller. This issue was addressed by the introduction of a velocity threshold and it is verified that the velocity threshold makes the PC more free from the noise effect at low velocity. Experimental results are presented for the “Excalibur” haptic device.
منابع مشابه
Passivity of a class of sampled-data systems: Application to haptic interfaces
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